When the Loco pilot should contact with SM on telephone while IBS in “ON” position? A. After 5 minutes B. After 2 minutes C. Immediate D. After 1 miutes in day and 2 minutes in night

The correct answer is C. Immediate.

The IBS (Intelligent Block System) is a safety system used in Indian Railways to prevent train collisions. When the IBS is in the “ON” position, the loco pilot must contact the station master (SM) on the telephone immediately. This is to ensure that the SM is aware of the train’s location and speed, and can take any necessary action to prevent a collision.

Option A is incorrect because it is not the correct time interval for contacting the SM. Option B is incorrect because it is not the correct time interval for contacting the SM. Option D is incorrect because it is not the correct time interval for contacting the SM during the day.